IS ETHANOL FOR THE LONG HAUL?

December 22, 2006

Although politicians are aggressively pushing ethanol from homegrown corn as a substitute for foreign oil, the conversion makes little energy sense, says New York Times reporter Matthew L. Waid, writing in Scientific American.

Ethanol production requires copious amounts of fossil fuels and even if 100 percent of the U.S. corn supply was distilled into ethanol it would supply only a small fraction of the fuel consumed by the nation's vehicles.

Studies show that producing ethanol from corn creates almost the same amount of greenhouse gases as gasoline production does; burning ethanol in vehicles offers little if any pollution reduction.

Deriving ethanol from cellulose -- cornstalks and the straw of grains and grasses -- consumes far less fossil fuel than ethanol from corn kernels:

But companies have had trouble coaxing the natural enzymes needed for conversion to multiply and work inside the large bioreactors required for volume production.

More promising organisms are being discovered; ethanol's long-term viability depends on their success.

Despite obvious drawbacks, U.S. Energy Secretary Samuel Bodman believes the technology might be commercially viable within five years. More companies should be lured in part by generous government incentives, even though no one seems quite ready to build on a commercial scale.

Source: Matthew L. Wald, "Is Ethanol for the Long Haul? Ethanol could displace gasoline, but it won't pay off until we find a way to distill cornstalks, not corn," Scientific American, January 2007.